1. Field of the Invention
The present invention relates to a ceramic capacitor which comprises a plate type ceramic member, electrodes formed on both major surfaces thereof and a resistor connected in series with the plate type ceramic member.
1. Description of the Prior Art
A capacitor for preventing oscillation of a power IC employed for, e.g., a radio receiver or a stereo receiver for an automobile is required to have relatively high equivalent series resistance of 1 to several .OMEGA., for example. However, equivalent series resistance of a ceramic capacitor itself is not sufficiently high. Thus, employed is structure for connecting a resistor in series with a ceramic capacitor.
As shown in FIG. 6, such a conventional ceramic capacitor 2 comprises a plate type dielectric ceramic member 4 and electrodes 6a and 6b formed on both major surfaces thereof. A resistor 8 is formed on one electrodes 6a by printing resistance paste, for example. Further, a connection electrode 10 for soldering is formed on the resistor 8, so that a terminal 14a is soldered and fixed to the connection electrode 10 through solder 12. On the other major surface of the ceramic member 4, a terminal 14b is connected to the electrode 6b similarly through solder. Coating resin 16 is applied to the ceramic capacitor 2 through dipping or the like, except for portions for extracting the terminals 14a and 14b.
As obvious from a equivalent circuit as shown in FIG. 7, relatively large equivalent series resistance R is formed in series with electrostatic capacitance C in the aforementioned ceramic capacitor 2.
However, the aforementioned conventional ceramic capacitor 2 has the following disadvantages:
(a) The equivalent series resistance R is formed in the direction of thickness of the resistor 8, whereby the thickness of the resistor is liable to vary and hence the resistance value is varied. However, it is difficult to correct the resistance value through trimming or the like since the electrode 6a is formed under the resistor 8.
(b) Since the terminal 14a cannot be directly soldered to the resistor 8, the connection electrode 10 must be provided for soldering the terminal 14a. Thus, the cost is increased by formation of the connection electrode 10. Further, the connection electrode 10 is inferior in adhesion to the resistor 8, whereby the same may be separated in the working process.